The ever-increasing deployment of Wi-Fi and ZigBee networks aggravates cross-technology interference (CTI) in the 2.4 GHz unlicensed spectrum. This letter presents a clean-slate technique, DOTA, to combat the CTI and enable ZigBee/Wi-Fi co-transmission. Unlike existing solutions merely handling Wi-Fi-to-ZigBee interference, DOTA accounts for the true sense of CTI wherein ZigBee and Wi-Fi interfere with each other. At the heart of DOTA lies two operations, signal polishing and pulse disambiguation, for decomposing and threading signal samples to recover contaminated ZigBee and Wi-Fi signals. Experiment results validate the feasibility of superiority of DOTA.